BRPI0614899A2 - fuel injection system for an internal combustion engine - Google Patents

Abstract

FUEL INJECTION SYSTEM FOR AN INTERNAL COMBUSTION ENGINE. With reference to figure 1, the present invention provides an internal combustion engine (10) comprising a combustion chamber with variable volume (13), an air intake system (18, 20, 21) for distributing intake air to the combustion chamber (13), an exhaust system (17) for relaying burnt gas from the combustion chamber (13) to the atmosphere, and a fuel injection system (19, 21, 22, 23, 24, 25, 26) to distribute fuel inside the combustion chamber (13) for combustion with the intake air. The fuel injection system (19, 21, 22, 23, 24, 25, 26) comprises a fuel injector (19) that functions as a positive displacement pump and dispenses a fixed amount of fuel for any and all injector operation (19), and a controller (23) that controls the operation of the fuel injector (19). In response to an increase in engine speed and / or load, the controller (23) increases the amount of fuel in the fuel injector (19). In response to a decrease in engine speed and / or load, the controller (23) reduces the amount of fuel distributed per engine cycle, reducing the number of times that the fuel injector (19) is operated per engine cycle. .

Description

"FUEL INJECTION SYSTEM FOR AN INTERNAL COMBUSTION ENGINE"

The present invention relates to a fuel injection system for an internal combustion engine.

Today, most in-house internal combustion engines use fuel injection systems to supply fuel to the engine's combustion chambers. Fuel injection systems have replaced previous carburetor technology because they provide more control over fuel distribution and enable the engine to meet emissions-related targets as well as improve overall engine efficiency.

Injectors in current use are modulated by pulse width. This means that each injector is operated for a chosen period of time in each engine cycle, the length of time the injector is open determining the volume of fuel delivered to the combustion chamber in that cycle. Typically, such pulse-width modulated fuel injection systems use a substantially constant fixed or precisely known pressure supply of fuel and open / close valves that can be activated for any length of time. predetermined under the control of an electronic controller. The result of such a combination of known pressure and variable but controlled opening times provides an injection of known quantities of fuel into the engine's combustion chambers. The above approach is accepted by all gasoline injection systems ( port injection system as well as direct) and also by the new technology comes from the high pressure "common pipe" diesel injection system. Occasionally, the new common duct direct injection diesel injection systems use multiple injection pulses to achieve better fuel dispersion in the cylinder, and this results in better combustion, but each pulse is of varying time (although much shorter than that of previous single-pulse fuel injection systems) and the controller will adjust the injector open time on each pulse to accurately control the amount of fuel delivered.

Therefore, all prior art systems require a pump, a throttle, an injector (which effectively functions as an open / close valve) and a sophisticated electronic control module to control each injector's open time. The injectors used in fuel injection systems are very accurate and fast in their responses (and not like previous fuel injectors that were slow in operation and lacking in competitiveness). Unpublished injectors are able to close close in less than one millisecond.

While the sophisticated and highly developed fuel injection systems currently available are ideal for use in car internal combustion engines, there are many other applications for internal combustion engines where such a level of sophistication is inappropriate and expensive. . For example, engines with a small single cylinder and low output power used for lawn mowers, power saws, small generators, motorized bicycles, scooters, etc. They are built for a very narrow cost target and have low output power, so they cannot afford the cost of a sophisticated fuel injection system or the power required to operate a fuel pump that supplies pressurized fuel. required by the sophisticated fuel injection systems available. To date, such small engines have used traditional carburetor technology. However, it is now the case that such small engines will face the same type of exhaust emission legislation as car engines, and must be modified in a way that meets the emission targets. Therefore, a cheap and simple fuel injection system is required for such small engines.

In a first aspect, the present invention provides an internal combustion engine comprising: a variable volume combustion chamber; an air intake system for distributing intake air to the combustion chamber; an exhaust system for relaying burnt gas from the combustion chamber to the atmosphere; and a fuel injection system for distributing fuel in the inter-combustion chamber for combustion with the intake air, wherein the fuel injection system comprises: a fuel injector acting as a positive displacement pump and dispensing an amount of fuel that is fixed for any and all injector operations; and a controller that controls the operation of the fuel injector; wherein: in each of at least a majority of engine cycles, the fuel injector is operated on a plurality of occasions by the controller; In response to increased engine speed and / or load, the controller increases the amount of fuel distributed per engine cycle, increasing the number of times the fuel injector is operated per engine cycle; and, in response to a decrease in engine speed and / or load, the controller reduces the amount of fuel distributed per engine cycle, reducing the number of times the fuel injector is operated per engine cycle.

In a second aspect, the present invention provides an internal combustion engine comprising:

a combustion chamber with variable volume;

an air intake system for distributing dead air to the combustion chamber;

an exhaust system for relaying burnt gas from the combustion chamber to the atmosphere; and

a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises:

a plurality of fuel injectors, each of which functions as a positive displacement pump and dispenses an amount of fuel that is fixed for all and any injector operation, at least one first fuel injector of plurality of fuel injectors dispensing a first an established amount of fuel other than a second established amount dispensed by a second fuel injector of the plurality of fuel injectors; and

a controller controlling the operation of each of the plurality of fuel injectors, wherein:

In each of at least most of the engine cycles the fuel injectors are operated on a plurality of occasions by the controller;

In response to increased engine speed and / or engine load, the controller increases the amount of fuel distributed per engine cycle, increasing the number of times fuel injectors are operated per engine cycle; and

In response to a decrease in engine speed and / or engine load, the controller reduces the amount of fuel distributed per engine cycle, reducing the number of times fuel injectors are operated per engine cycle.

In a third aspect, the present invention provides an internal combustion engine comprising:

a combustion chamber with variable volume;

an air intake system for distributing dead air to the combustion chamber;

an exhaust system for relaying burnt gas from the combustion chamber to the atmosphere; and

a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises:

a fuel injector that functions as a positive displacement pump and dispenses a fuel amount that is fixed for any and all injector operations; and

a controller that controls the operation of the fuel injector;

on what:

In each of at least most of the engine cycles, the fuel injector is operated on a plurality of occasions by the controller;

In response to increased engine speed and / or engine load, the controller increases the amount of fuel distributed per engine cycle, increasing the number of times the fuel injector is operated per engine cycle;

In response to a decrease in engine speed and / or engine load, the controller reduces the amount of fuel distributed per engine cycle, reducing the number of times the fuel injector is operated per engine cycle; and

The fuel injector comprises:

a housing in which a fuel chamber is formed, an electric coil; and

A piston that slides axially into a hole in the looper under the action of the electric coil to force fuel out of the fuel chamber, the piston by sliding between two end stops ensuring that the piston has an established travel distance every operation.

In a fourth aspect, the present invention provides an internal combustion engine comprising:

a combustion chamber with variable volume;

an air intake system for distributing dead air to the combustion chamber;

an exhaust system for relaying burnt gas from the combustion chamber to the atmosphere; and

a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises:

a plurality of fuel injectors, each of which functions as a positive displacement pump and dispenses an amount of fuel that is fixed to all and any injector operation, at least one first fuel injector from the plurality of fuel injectors dispensing a first fuel amount established different from a second fuel quantity delivered by a second fuel injector from the plurality of fuel injectors; and

a controller that controls the operation of the fuel injector;

on what:

In each of at least most of the engine cycles, the fuel injector is operated on a plurality of occasions by the controller;

In response to increased engine speed and / or engine load, the controller increases the amount of fuel distributed per engine cycle, increasing the number of times each fuel injector is operated per engine cycle;

In response to a decrease in engine speed and / or engine load, the controller reduces the amount of fuel distributed per engine cycle, reducing the number of times each fuel injector is operated per engine cycle; and

Each fuel injector comprises:

a housing in which a fuel chamber is formed;

an electric coil; and

A piston that slides axially into a hole in the looper under the action of the electric coil to force fuel out of the fuel chamber, the piston by sliding between two end stops ensuring that the piston has an established travel distance every operation.

In a fifth aspect, the present invention provides an internal combustion engine comprising:

a variable volume combustion chamber, an air intake system for distributing dead air to the combustion chamber;

an exhaust system for relaying burnt gas from the combustion chamber to the atmosphere; and

a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises:

a fuel injector that functions as a positive displacement pump and dispenses a fuel amount that is fixed for any and all injector operations; and

a controller that controls the operation of the fuel injector;

on what:

In each of at least most of the engine cycles, the fuel injector is operated on a plurality of occasions by the controller;

In response to increased engine speed and / or engine load, the controller increases the amount of fuel distributed per engine cycle, increasing the number of times the fuel injector is operated per engine cycle;

In response to a decrease in engine speed and / or engine load, the controller reduces the amount of fuel distributed per engine cycle, reducing the number of times the fuel injector is operated per engine cycle; the fuel injector is Mechanically driven by a cam action surface, the fuel injector comprising a piston actuated by a bias spring and displaceable by the cam action surface, with the piston moving in one direction by dragging fuel into an injector fuel chamber fuel and the movement of the piston in the other direction by forcing fuel out of the fuel chamber, the meat donor surface comprising a plurality of lobes, each of which can drive the piston during each cycle. engine, and the controller controlling how many of the meat lobes in each engine cycle cause the piston to e out of the fuel injector;

the fuel injector comprises a fuel outlet through which fuel is forced into the fuel chamber by the piston, and a fuel inlet through which fuel is introduced into the fuel chamber, the fuel injector having additional It is also a one-way inlet valve operable to allow fuel to flow into the fuel chamber from the fuel inlet, while also preventing backflow of fuel from the fuel chamber to the fuel inlet, and a one-way check valve. operable outlet to allow fuel to escape from the fuel chamber to the fuel outlet, while preventing backflow of fuel to the fuel chamber from the fuel outlet; and the one-way inlet valve can be disabled by the controller and, when disabled, allows fuel to flow out of the fuel chamber until the fuel inlet, piston movement when the first one-way valve is disabled serving only to drag fuel from the fuel inlet into the fuel chamber and then to expel the fuel out of the fuel chamber back into the fuel inlet.

In a sixth aspect, the present invention provides an internal combustion engine comprising:

a combustion chamber with variable volume;

an air intake system for distributing dead air to the combustion chamber;

exhaust system for air distribution of

intake to the combustion chamber;

an exhaust system for relaying burnt gases from the combustion chamber to the atmosphere; and

a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air;

wherein the fuel injection system comprises:

a plurality of fuel injectors, each of which functions as a positive displacement pump and dispenses an amount of fuel that is fixed to all and any injector operation, at least one first fuel injector from the plurality of fuel injectors dispensing a fuel amount different from a second fuel injector from the plurality of fuel injectors; and

a controller controlling the operation of each of the plurality of fuel injectors; on what:

In each of at least most of the engine cycles the fuel injectors are operated on a plurality of occasions by the controller;

In response to increased engine speed and / or engine load, the controller increases the amount of fuel distributed per engine cycle, increasing the number of times fuel injectors are operated per engine cycle;

In response to a decrease in engine speed and / or engine load, the controller reduces the amount of fuel distributed per engine cycle, reducing the number of times fuel injectors are operated per engine cycle;

each of the fuel injectors is mechanically driven by a meat action surface, each fuel injector comprising a piston actuated by a predisposition spring and displaceable by the meat action surface, with the piston moving in an inwardly dragging direction. fuel injector chamber and the movement of the piston in the other direction forcing fuel out of the fuel chamber, the cam action surface comprising a plurality of cam lobes, each of which may triggering the piston during each engine cycle, and the controller controlling how many of the lobes of meat in each engine cycle cause the piston to force fuel out of the fuel injector;

each fuel injector comprises a fuel outlet through which fuel is forced out of the fuel chamber by the piston, and a fuel inlet through which fuel is introduced into the fuel chamber, each fuel injector having additionally a first one-way valve operable to allow fuel to flow into the fuel chamber from the fuel inlet, while requiring backflow of fuel from the fuel chamber to the fuel inlet, and a second operable one-way valve to allow fuel flow out of the fuel chamber to the fuel outlet, while preventing fuel reflux into the fuel chamber from the fuel outlet; and

the inlet valve of each fuel injector can be disabled by the controller and, when disabled, allows fuel to flow back out of the fuel chamber to the fuel inlet, piston movement when the first one-way valve is disabled by serving only to drag fuel from the fuel inlet into the fuel chamber and then to expel the fuel into the fuel chamber back to the fuel inlet.

Preferred embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

Figure 1 is a schematic representation of an internal combustion engine with a fuel injection system in accordance with the present invention;

Figure 2 is a schematic illustration of a first type of fuel injector according to the present invention suitable for use with the engine of Figure 1;

Figure 3 is a schematic illustration of a second type of fuel injector suitable for nomotor use of Figure 1;

Figure 4 illustrates a modification of the fuel injector of Figure 3;

Figure 5 is a schematic illustration of a third type fuel injector suitable for nomotor use of Figure 1;

Figure 6 illustrates a modification of the fuel injector of Figure 5;

Figure 7 is a schematic illustration of a fuel injector type room suitable for use in the engine of Figure 1;

Figures 8a), b), c) and d) illustrate the operation of the fuel injector of Figure 7;

Figure 9 is a more detailed illustration of the fuel injector of Figure 7;

Figures 10a) to 10d) illustrate the operation of a modified fuel injection version of figures7 through 9;

Fig. 11 illustrates a one-way check valve for the fuel injector of Figs. 7 through 9;

Figure 12 illustrates a one-way check valve for the fuel injector of Figures 10a) through 10d);

Figure 13 illustrates a one-way check valve that can be used on the fuel injector (any of Figures 7 through 10d) in place of the illustrated check valves;

Figure 14 shows the type of signal used in prior art fuel injection systems to control the amount of fuel distributed to the combustion chamber in each engine cycle;

Figure 15 shows the control signal used by the present invention to activate the fuel injector of Figure 1 (for example, a fuel injector of any one of figures 2 to 10d) to control the amount of fuel dispensed into the chamber. - combustion chamber in each operating cycle;

Figure 16 shows in:

Figure 16a) a rotation signal taken from an engine shaft or crankshaft of the engine of Figure 1;

Fig. 16b) a control signal generated for full-load operation of the motor of Fig. 1;

Figure 16c) a control signal generated for partial load operation of the motor of Figure 1; Figure 16d) a control signal generated for slow operation of the motor of Figure 1; and on

Fig. 16e) a control signal generated during starting of the motor of Fig. 1;

Figure 17 is a schematic representation of the inlet passage of the internal combustion engine of Figure 1 with a slightly modified version of the fuel injector of Figure 3 in place;

Figure 18 shows a cross-sectional view of a fuel injector nozzle of Figure 17;

Fig. 19 shows a cross-sectional view of a part of the fuel injector of Fig. 17;

Figures 20a) to 20d) are schematic illustrations of the fuel injector operation of Figures 17 to 19;

Figures 21a) to 21d) show alternative shapes of the fuel injector nozzle orifice of figures 17a 20;

Fig. 22 is a schematic representation of a second embodiment of the internal combustion engine with a fuel injection system according to the present invention;

Fig. 23 is a schematic illustration of a fuel injector suitable for use with the engine of Fig. 22;

Figure 24 is a schematic illustration of the fuel injector of Figure 23 and its arrangement with a meat acting surface used to drive it; Figure 25 is a schematic illustration of a second embodiment of the fuel injector suitable for use. in the engine of FIG. 18 in place of the fuel injector illustrated in FIG. 18; and

Figure 26 is an illustration of a modification of the flesh action arrangement of Figure 24.

Turning first to FIG. 1, an internal combustion engine 10 comprising a cylinder 11 in which an alternating piston 12 with cylinder 11 and piston 12 defining a combustion chamber 13. Piston 12 is connected by FIG. a connecting rod 14 on a crankshaft 15 which, in turn, is connecting to a cam shaft 16. A mechanism (not shown), such as a depression rod mechanism, is used between the cam shaft 16 and two valves. 17 and 18 which are engine inlet exhaust valves. The camshaft 16 will drive the inlet valve 18 and the trigger valve 17 to open in synchronized relationship with the movement of the piston 12 in the cylinder 11 with return springs by biasing the gate valves 17 and 18 back to their seats valve The engine10 is a single engine, a single cylinder engine, for example a lawnmower or other garden equipment.

The engine 10 has a fuel injection system comprising a fuel injector 19 arranged to deliver fuel in an inlet passage 20 along with inlet valve 18. A bypass valve 21 is placed in inlet passage 20 to controlling the intake air flow into the combustion chamber 13. A sensor is connected to the bypass valve 21 and feeds the signal through a line 22 to an electronic control unit 23, the signal indicating rotational apposition. throttle valve 21 and therefore the engine load. The ECU 23 also receives a synchronization signal via a line 24, the synchronization signal being generated by a camshaft sensor 25 (which may be replaced by a crankshaft sensor). In consideration of the synchronization signal produced by sensor 25 and the load signal produced by the sensor attached to throttle valve 21, the ECU 23 generates a control signal which is relayed via line 26 to injector 19 and controls the operation of injector 19 .

A first example of injector 19 is shown in Figure 2. Injector 19 has a fuel inlet 30 in which a filter 31 is disposed to remove all impurities from the fuel before it passes into the main body of the injector. The main body 32 of the injector has a cavity 33 in which is located a stack 34 of piezoelectric elements. The fuel introduced by the inlet 30 passes along a passage 35 through the stack34. A flexible diaphragm 36 rests on a free end of stack 34 and diaphragm 36 incorporates a one-way valve 37 aligned with passage 35 through half stack 34. A section 38 of cavity 33 is defined by diaphragm 36. flexible cam 36 and exiting this section 38 is a fuel outlet passage 39 which is opened and closed by a one-way vane valve 40. Downstream of vane valve 40 is a high voltage electrostatic charging electrode 41 with openings allowing passage of fuel. Downstream of electrode 41 is a combustible output disc 42 with multiple fuel outlet holes defined therein. This disc 42 will also be charged to function as an electrode so that electrode 41 and disc 42 together apply a charge to the fuel passing through the injector, and this assists in the atomization of the fuel.

A simple gravity-fed fuel distribution system (not shown) will relay fuel from a fuel tank (not shown) to fuel inlet 30, the fuel being then filtered by filter 31. So, the fuel is drawn into the fuel injector of figure 2 and expelled from it by the expansion of the stack 34 of piezoelectric elements. When a voltage is applied to the piezoelectric elements of stack 34, they expand and this expansion causes stack 34 to increase in length and press flexible diaphragm 36. When this happens, the one-way valve 37 will close. and the fuel in section 38 will be forced out of section 38 by the flexed diaphragm 36, the diaphragm 36 flexing under the action of stack 34. The one-way valve 40 will open to allow fuel to be expelled from section 38 and, then the expelled fuel will pass through the holes in the charging electrode 41 and then through the holes in the fuel outlet disc 42 into the air inlet passage 20 (shown in figure 1). Fuel passing at electrode 41 and disk 42 will receive an electrostatic charge and this electrostatic charge will assist in atomizing fuel passing out of the holes in the fuel outlet disk 42.

Once the voltage is removed from the piezoelectric element stack 34, then the stack 34 will reduce to its original length and the flexible diaphragm 36, which is naturally resilient, will move back to its original position thereafter. thereby increasing the volume of section 38 of cavity 10 in the injector. This in turn will cause the one-way valve 40 to close to seal section 38 of the fuel outlet while the one-way valve 37 will open to allow fuel to flow through the passage35 to fill the fuel outlet. cavity 38. Then cavity 38 can be loaded with fresh charged fuel and ready for the next fuel injection in the air inlet passage 20.

In Figure 2, the control line 26 can be electrically connected to the piezoelectric element stack 34 and also electrically connected to the high voltage electrostatic charging electrode 41.

The fuel injector in Figure 2 operates with a positive displacement pump that, in any and all operation of the injector, dispenses the same amount of fuel. The volume of fuel distributed by the injector is constant for each operation. This varies significantly in injectors that act as open / close valves that control the flow of fluid through them, the fluid supplied to them being supplied from a pressurized source. Such injectors control the amount of fuel delivered by varying the injector opening time. There is no such variation in opening time with the injector of the present invention. Instead, it acts as a positive displacement pump and pumps out an adjusted fuel volume in any operation.

A second type of fuel injector suitable for operation as injector 19 of FIG. 1 is shown in Figure 3. Injector 19 in each and every operation distributes an established amount of fuel and the injector itself operates as a pump. to positively displace a volume of fuel from there, the volume remaining constant throughout any injector operation. Injector 19 is a single positive displacement pump with a solenoid driven piston sliding into a cylinder operating with a fixed displacement unit with two one-way check valves to ensure that fluid flow path occurs into and out of the injector. The injector acts as both a pumping unit and a flow measurement unit. The flow volume distributed by each pulse is a fixed geometry volume independent of the differential pressure across the injector, making the injector insensitive to fluctuations in the inlet passage. 20 from the input manifold.

The injector of FIG. 2 has a fuel inlet passage 50 that will be connected to a clobe-tasol tank (not shown) to receive fuel under a simple gravity feed arrangement (not shown). A spring-loaded one-way valve 51 controls the fuel flow from the inlet passage 50 into a fuel chamber 52 of the injector. A spring-loaded one-way valve 53 controls the flow of fuel out of the fuel cavity 52 to a fuel outlet pipe 54 through which fuel can be distributed (either directly or via a conduit to a spray nozzle). remote) into the air inlet 20.

A piston 55 is slidably located on the injector body. It is driven by a bias spring 56 and is surrounded by a solenoid 57. An end plate 58 is connected to piston 55 and extends radially out of the piston through an end face of solenoid 57. The solenoid 57 is connected by line 26 on ECU 23.

Assuming a condition in which the piston 55 is predisposed to its lowest point by the predisposition spring 56 (i.e., the point at which the fuel chamber 52 has its largest volume), the fuel chamber 52 will be prepared for use with fuel ready for injection. Then, energizing solenoid 57 acts to bring plate58 in or nearly in contact with solenoid 57. Piston 55 moves upward against the force of bias spring 56 to reduce the volume of the plate. 52. This causes positive fuel displacement of the fuel chamber 52, the one-way valve 53 opening to allow the piston 55 to expel fuel from the fuel chamber 52 through the fuel outlet 54.

Once solenoid 57 is de-energized, then bias spring 56 will force piston 55 down and plate 58 away from solenoid 57. Downward movement of piston 55 will cause the volume of fuel chamber 52 increase, and this will have the effect of closing the one-way valve 53 and opening the one-way valve 51. The moving piston55 drags fuel from the fuel inlet 50 into the fuel chamber 52 to fully charge the chamber 52 to get ready for the next fuel distribution.

The injector is constructed so that the piston 55 has a displacement distance set in each operation. Opiston 55 moves between two end stops. Thus, in any injector operation, the piston 55 displaces an established amount of fuel and a set amount of fuel is dispensed by the fuel outlet 54. The amount of fuel dispensed by the injector is constant for any operation.

Commonly, a typical fixed volume of fuel dispensed by the injector is within 0.1 μΐ; and 1 μι, but typically less than 0.5 pL. Typically, the injector may operate at frequencies from 300 Hz to more than 1 KHz, preferably from 1 KHz to 2 KHz. Such an operating volume and frequency is suitable for many engine capacities in the small engine market.

The operating principle of the injector of figure 3 is to distribute a geometrically fixed volume of fluid to each actuation pulse. Since engines of different capacities and output power will have different fuel consumption rates, it is necessary to optimize the pulse volume to best suit the individual engine.

In order to manufacture the injector of Figure 3 in large scale and therefore at the lowest possible cost, it is advantageous to have an injector size that will fit a wide range of different engine sizes. In order to achieve this, the injector piston stroke can be easily adjusted during manufacture by installing a shim to give the desired pulse volume for the specific application of each injector.

Figure 3 shows an injector without a shim that results in the maximum possible stroke of piston 55 in each pulse. The same injector with a shim 59 installed is shown in figure 4. By using shim 59, piston stroke 55 is reduced, allowing the injector to be optimized for a smaller engine capacity. The injector dispensing volume is still geometrically fixed and can be repeated for each actuation during its operation.

The key feature is that the displacement of the injector is always a constant geometric volume to ensure accuracy of fuel distribution when in use on an engine. But the use of shims allows for large-scale e-fetal manufacturing in costs of substantially identical injector units that can be easily configured to fit a wide range of motors in the last stage of manufacture.

Figure 5 shows a fourth embodiment of the injector according to the present invention. As with the embodiments of figures 3 and 4, the injector comprises a movable piston 500 under the action of a biasing spring 501 and a solenoid 502. Piston 500 is slidable into a 503 fuel chamber. A one-way inlet valve 504 allows fuel to be drawn into fuel chamber 503 from a fuel inlet 505, but prevents fuel from being expelled from the chamber. 503 through the 505 fuel inlet. A one-way outlet valve 506 allows fuel to be expelled from the fuel chamber 503 through a fuel outlet 507, but prevents fuel from being drawn into the fuel chamber 503 through the fuel outlet 507.

Unlike the embodiments of FIGS. 3 and 4, the injector of FIG. 5 uses spring 501 to force piston 500 to expel fuel from fuel chamber 503 through fuel outlet 507 and uses solenoid 502 to move piston and drag fuel inwardly. of the fuel chamber 503 (i.e. the reverse of the embodiments of figures 3 and 4). Piston 500 has an end plate 508 that extends radially out of piston 500 through an end face of solenoid 502. Displaced fuel volume, spring constants, etc. they will be the same or similar to those described above.

Figure 6 shows a modification of the embodiment of Figure 5 in which a shim 509 is provided in the fuel chamber 503 to limit piston displacement 500 and thereby adjust the amount of fuel dispensed at each injector operation. Shim 509 has an opening for allowing communication of fuel chamber 503 with outlet valve 506 and fuel outlet 501. In the foregoing, the use of shims allows for a manufacturing process in which substantially identical injector units are made. with different fuel output volumes by selecting properly sized shims.

In Figures 4 and 6, shims 59, 509 shown are attached to the injector housing, however, a shim may be installed on both pistons 55, 500 instead of or in addition to illustrated shims 59, 509.

Figure 7 shows an injector 700 with a piston 701 located in the center of a solenoid 702 and a supporting metal screen 703. The supporting metal screen is designed to direct magnetic flux around the solenoid turns. 701 is fitted with the 703 supporting metal screen when solenoid 702 is energized. A piston spring 704 pushes piston 701 away from supporting metal screen 703 when the solenoid is de-energized. A fuel inlet check valve 705 is located in a fuel passage through the piston701. The fuel passage allows fuel to flow through the piston to a fuel chamber 706. Fuel is dispensed from the fuel chamber 706 to a fuel outlet 707 via an outlet check valve 708. Advantageously at the injector of figure 7 , movement of piston 701 assists in the operation of inlet check valve 705 as shown in figures 8a) to 8d). Figure 8a shows piston 701 in its nabase stop position. The ball mass in check valve 705 assists its own spring to close inlet check valve 705, thereby sealing fuel chamber 706.

When the solenoid coil 702 is energized with an electric current, as shown in Figure 8b), piston 701 is dragged upward by the magnetic flux flowing from the supporting metal lane 703. In this motion, the inertia of the inlet retention sphere drives the ball firmly in contact with its seat, which ensures an airtight seal inlet valve 705, and thus ensures that all ex-fluid fluid from fuel chamber 706 flows out through half outlet check valve 708. When the piston 701 reaches its upper position (shown in Figure 8c) and the fuel pulse volume has been expelled, the piston 701 will be rapidly disrupted by its end stop. However, the inlet check valve ball 705 will continue upward at its own momentum and will open inlet check valve 705. At this time, solenoid 702 is de-energized and piston spring704 pushes the piston 701 down.

As shown in figure 8d), the piston 701 moves downward driven by its own spring. The inlet ball check valve 705 lags behind due to its mass inertia as well as the fuel flow force and, in this condition, will allow fluid to easily flow into the fuel chamber 706 and the area. -supply as piston 701 continues to move downwards.

When the piston 701 reaches its base stop it will be quickly stopped again and the inlet check ball 705 will be thrust into contact with its seat again, depending on its momentum force, as shown in figure 8a).

In this way, opening and closing of inlet check valve 705 is assisted by movement of piston 701. This allows the injector to be driven at a higher frequency than would otherwise be possible.

Figure 9 shows a more detailed sectioned drawing of the injector of figures 7 and 8a) to 8d). Inlet check valve 705 may be viewed comprising a ball 710 and a spring 711.

Typically, the spring rate of spring 711 of the inlet check valve 51 is chosen in the range 0.4 N / m 1.75 N / mm to allow the seat ball to be raised from its seat during the inlet stroke, displacement dopist typically being 50 to 150, for example 100 µm. Inlet check valve 51 is shown in figure 11 comprising a ball 710 and a spring 711.

With the location of the check valve entering a fuel passage in the piston, it is possible to perform without a check valve spring, as shown in figures 10a) to 10d and figure 12. The valve retention insert 7000 comprises (see Figure 12) a movable ball 7001 in a housing 7002. The housing 7002 permits fluid flow, but keeps the ball 7001 trapped in overlap. The function of valve 7000 is exactly as described for valve 705, but the mass inertia of ball 7001 is based on being the unique opening and closing device of valve 7000. This can be seen in figures10a) to 10d), where Ball motion and piston motion are indicated by arrows, as is the direction of the flow flow. In figure 10a), the movement of the ball 7001 forces the valve closed. In Figure 10b), the mass inertia of ball 7001 raises the ball away from the seat as the piston moves downward (the pressure differential flowing through the valve also has a function). In figure 10d), it can be seen that housing 7002 prevents ball 7001 from moving too far from its seat during downward movement of the piston. Using a valve without a valve reduces costs and assembly time. A disk may be used instead of a ball and this is illustrated in Figure 13 where a disk is movable in a housing 7011 (this valve will operate in the manner described above for valve 7000). Using a disc can reduce the volume of fluid trapped in the fluid flow through the piston above the valve and make the arrangement less susceptible to trapping gases.

The control of the injectors of the present invention is completely different from the control of the prior art injectors, as will now be illustrated in figures 14, 15 and 16a) to 16d). In figure 14, a graphic illustration of a control signal used can be seen. to control a previous datech gun. The mode of operation used is called pulse width modulation control. In solid lines a pulse of a chosen width can be seen and corresponds to the opening duration of a traditional fuel injector. Dotted lines show other larger pulse widths, that is, longer durations of traditional prior-art nozzle openings. With an adjusted delivery pressure, thrust width control gives exact control of the amount of fuel delivered by the fuel injector.

Moving to Fig. 15, Fig. 15 graphically illustrates the control signal generated by ECU 23 to control fuel injector 19 in the present invention. Instead of pulse width modulation, a control form called pulse count injection is used. It can sever in solid lines six different pulses. There are pulses for a single engine operating cycle, that is, the distribution of charged fuel for a single combustion event in the combustion chamber 13. Each pulse represents an operation of injector 19. In the foregoing, by virtue of In each and every operation distributing an established amount of fuel, the total amount of fuel distributed for combustion is controlled by controlling the number of injector operations for a particular engine operating cycle. In the case illustrated in solid lines, the injector 19 is operated six times to deliver a total amount of fuel equal to six times the established amount distributed by the injector in each operation. This fuel is distributed into the air inlet passage 20 for mixing with air to be dispensed into the combustion chamber 13. The first operation of the injector 19 will occur while the inlet valve 18 is closed, but may unless the valve is open or has at least begun to open at the time of the last injector operation 19.

In Figure 15, the dotted line pulses show that a larger amount of fuel can be distributed in the duty cycle by operating the injector a greater number of times. Figure 15 illustrates a total possible pulse count of 10 pulses, giving a total amount of distributed fuel of 10 times the set amount distributed by the injector in each operation.

Further details are given in Figures 16a) to 16e). Figure 16e) shows the signal from the meat shaft or crankshaft received on line 24 by the ECU 23. The pulses shown in the signal give an indication of the rotational position of the crankshaft. or the meat shaft. It can be seen that the ECU 23 determines the timing of its own pulses in the control signal it elects to be synchronized with the pulses in the sync signal shown in Figure 16a) which triggers the ECU 23 to stop its own control pulses. shown in figure 16b) to 16e). Alternatively, the sync signal pulses can be generated internally on the ECU23, with only one pulse motor power cycle out of sync from a crankshaft or crankshaft sensor.

Figure 16b) shows full load operation. Therefore, in each engine cycle (one engine cycle occurs between the dotted lines in the figure), the ECU generates a control signal shown in figure 16b) comprising thirteen pulses operating the injector 19 times. This represents the maximum amount of fuel that can be distributed for combustion in the combustion chamber 13.

Figure 16c) shows the control signal generated at each motor cycle for partial load operation. In this case, the control signal in each cycle comprises seven pulses operating injector 19 seven times in each engine cycle. Thus, the amount of fuel distributed in each engine cycle is 7/13 of the total amount of fuel that is distributed in full load operation.

Figure 16d) shows the control signal generated by the ECU through slow operation, that is, the moment when the least amount of fuel is distributed in each engine cycle. Figure 16d) shows that injector 19 is operated only 4 times in each engine cycle.

Finally, Figure 16d) shows an exceptional engine starting condition in which a rich mixture of fuel and air is distributed into the combustion chamber 13 to enable engine starting. Sixteen pulse counts are shown for each cycle of the mobile terminal and this means that the injector 19 is operated seventeen times through each engine cycle at the time of the engine starting. Total fuel distributed is seventeen times the established amount that the injector distributes in each operation.

The above engine is noted to remove the need for a separate fuel pump, and a throttle dramatically simplifies the function of the ECU. The fuel injection system comprises a simple control system that counts the desired number of fuel pulses within the engine for proper operation. Although this does not provide the degree of control possible as a prior art system (ie the total fuel volume) can not be varied continuously over a range, but only at set intervals or adjusted quantities), this will suffice for a single engine such as that used on a lawn mower. To put it another way, the control possible with pulse count injection provides rough control of the amount of fuel distributed to the engine, but will be sufficient for the simple engines involved.

As described above, the fuel delivered by the injector may be passed to a flat or simple nozzle (see Figure 2) or may be passed through an atomizing device such as a pressure spray nozzle (described below with reference to FIGS. 17, 18,19, 20a) to 20d) and 21a-21d)) or an electrostatic charging unit (shown in Figure 2). The injector (or pulse unit) may be coupled closed to the atomization unit or located elsewhere on the somewhat out of the engine (ie, the embodiment of figure 3 may have a fuel outlet leading to a nozzle). distribution a bit away from the injectors shown).

The volume of fuel distributed by the fuel injector depends to some extent on the size of the engine and the range of engine operating conditions. Typically, an injector will distribute between 0.03 mm3 and 0.08 mm3 per pulse. If a range of 0.01 mm3 to 0.05 mm3 per pulse is considered, then typically the total volume distributed in each engine cycle will be between 0.5 and 10.0 mm3. If this is the case, then the number of pulses required for proper engine operation will range from five to ten pulses per engine cycle for slow engine operation, and from twenty to fifty pulses per cycle for full load operation. .

Since the injector itself controls the amount of fuel delivered, there is no need for a controlled fuel supply pressure, and this means that fuel can be fed directly to the injector via a gravity feed system without any problem being caused by pressure change in function of different fuel height as fuel level drops. Alternatively, a simple low pressure fuel pump often used with carburetors may be used. The only requirement is that enough fuel be distributed to the injector so that it can recharge for the next pulse.

The total amount of fuel delivered to the engine in each cycle (every two strokes on a dual stroke engine or every four strokes on a four stroke engine) is determined as a multiple of the fuel volume expended on each injector operation and the number times the injector is operated in the cycle. The power management system can be built simply to distribute a different number of pulses on your control signal depending on the required motor load demand measured by sensor 21. Therefore, it can be constructed from only a few circuit chips. integrated a very simple electronic control unit that compares the position of the accelerator measured by sensor 21 (eg a throttle position potentiometer) with a lookup table giving the number of pulse counts required for that throttle position and with the ECU then generates pulses triggered by the synchronization signal on line 24 and counting the number of pulses until the correct number of pulses is reached. Then the pulse injector is turned off until the next domotor cycle.

Turning to Fig. 17, an accelerator body 202 of an internal combustion engine is shown. Accelerator body 202 includes an inlet passage portion 200 of the inlet passageway 20 of FIG. 1. The inlet passageway portion 200 communicates at one end 204 with the combustion chamber 13 of the engine via the inlet valve 18, and at the other end. 206 with atmospheric air, typically by means of an air filter (not shown). In the inlet portion 200 is located a throttle valve 21 and downstream of the throttle valve 21, between throttle valve 21 and inlet valve 18, there is a fuel injector 19 of the type previously illustrated in figures 3 to 13.

In the arrangement of figure 17, fuel dispensed from the fuel chamber 52 is dispensed to the fuel outlet 214 comprising, in the embodiment of figure 13, a mixing chamber 218 and an atomizing nozzle 214. To assist in the production of a fuel mixture and charged that will be burned quickly when ignited in the combustion chamber, the fuel must be effectively mixed with the intake air. Conventional carburetors and fuel injectors achieve this by having a number of nozzles at the nozzle end to form a fine nozzle fuel spray in the intake air. The atomization nozzle 214 of the present invention is a sonic nozzle (also known in technology as a critical flow hazard or critical flow nozzle). The atomizing nozzle may also be an air jet nozzle.

Frequently, sonic nozzles are used as fluid flow patterns as they provide a constant volumetric flow rate, since their pressure differential exceeds a predetermined limit value. A schematic diagrams of a sonic nozzle is shown in FIG. 18. The nozzle comprises a venturi 350, the internal dimensions of which narrow to provide a neck. Fluid upstream from the venturi neck is at a higher pressure than that downstream from the venturi neck. Fluid flowing into the nozzle is accelerated in the region of the narrow neck. The velocity of the fluid in the neck approaches the speed of sound. Once this condition has been met, the sonic nozzle rate will remain constant even if the downstream pressure varies significantly, provided that the pressure differential across the nozzle certainly exceeds the limit value. Thus, in the present example, a constant fluid flow to the intake air is achieved. It should be understood that a sonic nozzle will provide a constant flow regardless of the suddenness of the change in downstream pressure, provided that the downstream pressure remains at less than about 85-90% of the upstream pressure.

In the present invention, the passage of fuel through the sonic nozzle 214 assists in the dispersion of the fuel in the intake air. Indeed, as the speed of fuel passing through the neck 302 approaches the speed of sound, the nozzle 214 acts as a highly efficient atomizer by shattering liquid fuel into a tiny particle vapor. In general, the finer the spraying of fuel into the intake air, the better the combustion process achieved. Although the exact operation of sonic nozzles in fuel atomization is not well understood, it is thought that the passage of liquid fuel by half-shock waves in the high velocity region of the sonic nozzle will produce very high shear stresses on the surface. -cie liquid and cavitation bubbles in the liquid, both of these processes leading to very fine atomization and dispersion of the fuel in the intake air.

Mixing chamber 218 is located between outlet check valve 53 and nozzle 226. As can be seen from Figure 17 and the enlarged view of Figure 19, throttle body 202 also comprises an air bypass passage 240. This consists of: a passage that communicates with both the mixing chamber 218 and a region where the air is at atmospheric pressure.

Fuel dispensed by injector 19 passes through the mixing chamber 218 and through the sonic nozzle 226.Low pressure in the inlet passage 200 also drags air through the air bypass 240. Thus, air flows through the air bypass nozzle. 240 and carries the fuel dispensed by the injector 19 into the mixing chamber 218. The air bypass 240 is at a higher pressure than the inlet port 200 and therefore as fuel is dispensed from the nozzle 214, it is charged into the air flow of passage 240 through sonic nozzle 214 within the inlet passage 200. This causes the dispensed fuel to be atomized.

Figures 20a) through 20d) show the operation of the "air assisted" sonic atomizer for a door fuel injector across the engine cycle for two different engine loading conditions.

Injector 19 distributes the fuel and controls the amount of fuel. The movement of air in the inlet door generates the effect of atomization. This allows each process to be fully optimized to achieve maximum effect with minimum energy.

In figures 20a) to 20c), fuel is introduced into the mixing chamber 218 during the engine cycle period when the engine inlet valve 18 is closed. Under these conditions (whatever the load) there is little air movement and then the fuel delivered over a period of time through the engine cycle will accumulate in this chamber. As the engine inlet valve 18 opens, air is drawn through the inlet port and into the combustion chamber 13. In a partial loading condition shown in Figures 20a) and 20b), throttle 21 is partially closed and air flow will cause a pressure difference across throttle 25. In a full load (fully open throttle) condition shown in figures 20c) and 20d), the velocity of the throttle at this time creates a drop in pressure. neck pressure 302 doventuri.

With an accumulated volume of fuel in the mixing chamber, air flowing through the bypass passage 240 begins to cause fuel effervescence, and as the speed of air flow and charged fuel increases in sonic nozzle 214 (due to the smaller area cross shear forces) large shear forces are created leading to excellent fuel atomization as it is blown into the inlet port.

This process not only generates a well atomized fuel spray, but has the advantage that its synchronization coincides with the inlet valve 18 being opened, so the fuel taken directly into the combustion chamber 13 and is not deposited in the chamber. network of the entrance door. Also, this synchronization effect allows the remainder of the engine cycle for fuel metering inside the mixing chamber 218, thus allowing lower pressure injectors to be used without their inherent atomization faults causing any fuel problems. poorly atomized.

In this way, very well atomized fuel is distributed in the best engine synchronization with the minimum energy rest.

Better fuel atomization at the inlet port improves air fuel mixing and therefore improves combustion process in the engine resulting in lower emissions and lower fuel consumption as well as easier starting for smaller engines.

Air bypass 240 is not limited to the air supply, but may alternatively be connected to a gas supply to provide an alternative gas to aid in atomization or combustion. An example of another such gas that can be used is engine exhaust gas (ie exhaust gas recirculation).

The sonic nozzle 214 may comprise different deformed holes, as shown in figures 16a) through 16d). The hole in a standard sonic nozzle, when a cross section is taken perpendicular to the direction of flow, is circular as shown in Figure 16a. Alternative shapes of the nozzle holes comprise a linearly extended orifice shown in Figure 16b, a cruciform shape shown in Figure 16c) or, alternatively, a group of smaller circular holes shown in Figure 16d.

Figure 22 shows a further embodiment of the engine according to the present invention, the engine having a mechanically driven injector that is electrically controlled instead of an above described electrically driven injector.

Figure 22 shows an internal combustion engine 80 comprising a cylinder 81 in which a piston 82 alternates with cylinder 81 and piston 82 defining a combustion chamber 83 therebetween. Piston 82 is connected by a connecting rod 84 on a crankshaft 85 which, in turn, is connected to a meat shaft (not shown) with meat, by its meat actions, operate two trigger valves87 and 88 which are the domotor exhaust and inlet valves. These valves are opened and closed in synchronous relationship with piston 82 and cylinder 81. Non-return springs (not shown) will be provided to bias trigger valves 87 and 88 to their valve seats. The Omotor 80 is a simple engine, for example, a single-cylinder engine from a lawnmower or other garden equipment. The engine 80 has a fuel injection system which comprises a fuel injector 90 arranged to dispense fuel within the inlet port 89 upstream of the inlet valve 88. A throttle valve 91 is disposed in the inlet port 89 to control the flow. supply air into the combustion chamber 83. A sensor is connected to the throttle valve 91 and generates a signal indicating the throttle valve position 91 which is supplied as an electrical signal to an engine control unit 92

The fuel injection system of Fig. 22 comprises a meat action surface 93 provided on a circumferential surface of a wheel 94 mounted on and rotating with the turnbuckle 85. A fuel injector96 is driven by the meat action surface 93 and is shown in more detail in figure 23.

In figure 23, it can be seen that the fuel injector 96 comprises a fuel inlet 97 receiving fuel fed from a fuel tank (not shown) by a gravity feed system (not shown). Fuel may pass from the fuel inlet 97 into a fuel chamber 98 with fuel flow controlled by a first spring-loaded one-way valve 99. A second spring-loaded one-way valve 100 controls the flow of fuel out of the fuel chamber 98 to a fuel outlet 101. The fuel outlet 101 is connected by a fuel line 102 (see figure 22) to the nozzle and atomizer 90.

A piston 102 is slidably mounted in a nozzle housing 103 and is slidable in the fuel chamber 98. The piston 102 has a cam follower 103 which is a roll follower rotatably mounted on one end of the piston 102. The roller follower 103 will engage with the flesh action surface 93 and follow it (see Figure 22). Piston 102 and thus roller follower 103 are arranged in engagement with the cam action surface 93 by a biasing spring 104 acting between the injector body 103 and a shoulder 105 provided to extend radially outwardly of the piston 102.

Also provided in injector 96 is a control solenoid 106 which is electrically controlled by a signal provided on a line 107 along which control signals from the motor control unit 92 pass. Solenoid 106 may act on an overlap pin 108 comprising a rod 113 extending via solenoid 106 and a disc 109 extending radially outwardly of rod 113about one end of control solenoid 106.

In injector operation (and starting from a condition in which piston 102 occupies a position in which fuel chamber 98 has its largest volume and considering that fuel chamber 98 is fully charged with a fresh charged fuel), piston 102 will be pushed into the chamber 98 under the action of the meat action surface 93. Therefore, the. piston 102 will displace fuel from chamber 98 which will flow out of the fuel outlet101, the one-way valve 100 opening to allow fuel to be dispensed from the fuel chamber 98 at a time when the one-way valve 99 seals the fuel inlet 97 of the fuel 98. The fuel forced out of the fuel chamber 98 will pass along the fuel line 102 to the nozzle 90 to be dispensed as a spray in the inlet passage 89. Subsequently, the piston 102 (following surface operfil 93 and under the action of the predisposed spring 104) will move to increase the volume of the fuel chamber 98. This will have the effect of closing the one-way valve 100 at the opening of the one-way valve 99. Then fuel will be dragged to the interior. from fuel chamber 98 from fuel inlet 97 until a maximum value of fuel is reached, then the process will be restarted.

In Fig. 24 the injector 96 can be seen interacting with the meat action surface 93 and it can be clearly seen that the meat action surface 93 comprises pulse lobes, such as 110, separated by base circle regions, such as 111, typically, the pulse lobes have a crest with a radius 0.1 to 0.5 mm larger than the base circle. It is seen from Fig. 10 that the wheel 94 has a total of pulse vintelobules and also a constant radius section 112. When the roller follower 103 fits into section 112, then the pulse injector 116 is deactivated.

If the control solenoid 107 is kept disabled for an entire engine cycle, then each of the pulse lobes (eg 110) on the decking action surface will result in the distribution of a quantity of fuel from the injector. 96. The injector 96 will dispense twenty separate fuel pulses for each complete rotation of the wheel 94. It should be understood that each pulse lobe 101 will have a height relative to the base circle that is identical to all other lobes of each piston 102 to move a set amount so that the amount of fuel dispensed by the injector 96 is the same in any and all operation of the injector 96, that is, for any and all fuel distribution of the injector 96. The operation of the injector 96 twenty times for wheel casing 94 represents distribution of the maximum possible fuel volume to the engine in each operating cycle, a condition as being used, for example, in the engine

Control solenoid 107 enables injector control 96. When solenoid 106 is energized, then opino 108 will engage the one-way valve 99 and will force it to open and keep it open. When the one-way valve 99 is opened, then movement of the piston 102 results in drag into the fuel chamber 98 from the fuel inlet 97 and then into the fuel expelling from the chamber 98 return to the fuel inlet 97. No fuel is expelled from chamber 98 via the one-way valve 100. Thus, the ECU can control the operation of the injector 96 and can control how many fuel pulses are distributed by the injector 96 and, consequently, the total amount of fuel distributed in each engine cycle (each of the courses on a two stroke engine or every four courses on a four stroke engine).

In figure 25, one can see an injector 150 that can be used in the engine of figure 7 in place of the injector 96 shown in figure. Injector 150 comprises a fuel inlet 151 which receives fuel fed to it from a fuel tank (not shown) by a gravity feed system (not shown). Fuel can be moved from fuel inlet 151 to the interior of a fuel chamber 152 with the fuel flow controlled by a first spring-loaded one-way valve 153. A second spring-loaded one-way valve 157 controls fuel flow to forced fuel chamber 152 up to a fuel outlet154. Fuel outlet 154 will be connected by fuel line 120 of FIG. 7 to the dispensing nozzle and to the tomizer 90.

A resilient displacement diaphragm 155 seals the fuel chamber 152. Diaphragm 155 is provided with a meat follower contact pad 156. The contact pad 156 will engage the meat action surface (not shown) and follow it. The contact pad 156 is prone to engagement with the meat action surface by the resilience of the diaphragm 155. The meat action surface will be naturally variable under the control of the ECU 92 in order to dispense a variable number. for contact pad 156. This will be achieved, for example, by mounting a second control wheel 95 beside the rotatable meat wheel 94 with the meat wheel 94, but also rotatable with respect to the meat wheel 94 under control. ECU Such an arrangement of the cam wheel 94 and the control wheel 95 is shown in Figure 26. The control wheel 95 has a primer 95a with a periphery of a constant radius equal to the radial distance to the peak of each lobe 110 of the wheel. 94, and a second sector 95b with a periphery of a constant equal to the radial distance to the base of each base circle region 111 of the meat wheel 111. At one end, the second sector 95b of the control wheel 95 aligns with all lobes. and base circle sections of the flesh wheel 94 and all of them are active in displacing the diaphragm 155. Then, as the control wheel 95 and the flesh wheel 94 are rotated relative to each other, the first sector 95a the control wheel aligns with some of the lobes of the meat110 and base circle sections 111 and "disables" them as the greater radial height of control wheel 95 "overlaps" the base circle parts 11 of wheel 11. meat 94.

In operating injector 150 (and starting from a position in which diaphragm 155 occupies a position in which the fuel chamber 152 has its maximum volume and considering that the fuel chamber 152 is fully charged with fresh charged fuel), the the diaphragm will be bent under a cam 110 to reduce the volume of the fuel chamber 152 and thereby move fuel from chamber 152 to flow out of the fuel outlet 154 the one-way valve 157 opening to allow fuel distribution from the fuel chamber 152, while the one-way valve 153 seals the fuel inlet 151 of the fuel chamber 152. The forced fuel out of the fuel chamber 152 will pass along the fuel line 120 up to the nozzle 90 to be dispensed as a spray in the air inlet passage. Subsequently, the diaphragm 155 (according to the profile of the meat acting surface and depending on its own resilience) will flex to increase the volume of the fuel chamber 152. This will have the effect of closing the one-way valve 157 during opening the one-way valve 153. Then , fuel will be drawn into the fuel chamber 152 from the fuel line 151 until a maximum volume is reached, then the process will be restarted.

At each engine operating cycle, the diaphragm155 will be flexed to expel fuel from the fuel chamber 152 for each operable meat lobe in that cycle, the number of operable meat lobes being selected by the ECU, for example, by rotating the control wheel. in relation to the wheel of flesh.

As with the engine of figure 1, the engine of figure 22 does not need a high pressure pump to pressurize fuel supply or a pressure regulator to control the fuel pressure delivered. The engine also does not need a sophisticated ECU to control the operation of a fuel injector. Instead, the ECU can be constructed from simple integrated circuit chips that together select the appropriate number of thrusts for a given motor load (perceived by motor load sensor 91) and then count the number of pulses distributed in one. engine cycle before disabling the injector.

With the engine of Fig. 32, it may still be possible to arrange a mechanical control for injector 96 by some connection between the throttle and injector 96. In all exposed engine modes, only a single injector was used for each cylinder in operation. of the engine. However, the applicant realizes that each working cylinder can be provided with a plurality of injectors. This can have two advantages. First, in order to distribute a given amount of fuel in each engine cycle, the number of operations of each individual injector will be decreased and this can have practical benefits since each injector will not need to operate at such high speed in use. Second, if the injectors for a particular functioning cylinder are built so that they deliver a different amount of fuel to each other, then the engine management system can control the operation of both in a way that will have "finer" control. amount of fuel distributed during each operating cycle. For example, if an engine is fitted with a single injector that injects 0.1 mm3 per pulse, then the total fuel injected per engine cycle must be a multiple of 0.1 mm, ie 0.1 mm, 0.2 mm3, 0.3 mm3 to 0.5 mm3. However, if an engine is fitted with two injectors, one that injects a pulse of 0.1mm3 and the other that injects a pulse of 0.05mm3, then the engine will be able to distribute, in each engine cycle, a quantity Total fuel which can be 0.05mm3, 0.1mm3, 0.15mm3, 0.2mm3, etc. This is achieved with the least number of injector operations that would be required if the operating cymbal had only one injector capable of a 0.05 mm pulse.

Claims (47)

1. an internal combustion engine, characterized in that it comprises: a variable volume combustion chamber, an air intake system for distributing dead air to the combustion chamber, an exhaust system for relaying burnt gas from the combustion chamber to the atmosphere; a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises: a fuel injector that functions as a positive displacement pump and dispenses a fuel amount that is fixed for any and all injector operations; a controller controlling the operation of the fuel injector, wherein: in each of at least most of the engine cycles the fuel injector is operated on a plurality of occasions by the controller in response to an increase in engine speed and / or engine , the controller increases the amount of fuel distributed per engine cycle, increasing the number of times the fuel injector is operated per engine cycle; In response to a decrease in engine speed and / or engine load, the controller reduces the amount of fuel distributed per engine cycle, reducing the number of times the fuel injector is operated per engine cycle. 2. Internal combustion engine, characterized in that it comprises: a variable volume combustion chamber, an air intake system for distributing dead air to the combustion chamber, an exhaust system for relaying burnt gas from the combustion chamber to the combustion chamber. atmosphere; a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises: a plurality of fuel injectors, each of which functions as a positive displacement pump and dispenses an amount of fuel that is fixed for all and any injector operation; fuel of the plurality of fuel injectors dispensing a first established amount of fuel other than a second established amount dispensed by a second fuel injector of the plurality of fuel injectors; a controller controlling the operation of each of the plurality of fuel injectors, wherein: in each of at least most of the engine cycles the fuel injectors are operated on a plurality of occasions by the controller in response to an increase From engine speed and / or engine load, the controller increases the amount of fuel distributed per engine cycle, increasing the number of times the fuel injectors are operated per engine cycle; In response to a decrease in engine speed and / or engine load, the controller reduces the amount of fuel distributed per engine cycle, reducing the number of times fuel injectors are operated per engine cycle. 3. Internal combustion engine, according to claim 1, CHARACTERIZED by the fact that the fuel injector uses electric energy to dispense fuel and the controller is an electronic controller that produces a pulsed control signal to control each and every fuel injector, each pulse making. cause the / each fuel injector to dispense fuel and the electronic controller varying the number of pulses per engine cycle to vary the amount of fuel dispensed. 4. Internal combustion engine according to claim 3, characterized in that the / each fuel injector comprises a stack of piezoelectric elements which, in increasing length, forces the fuel out of the fuel injector. 5. Internal combustion engine according to claim 3, characterized in that the / each fuel injector comprises an electric coil. 6. Internal combustion engine according to claim 4 or 5, characterized in that the / each fuel injector comprises a housing in which a fuel chamber is formed, from which chamber the fuel is forced out of / each fuel injector, the / each fuel injector having a fuel inlet for admitting fuel into the fuel chamber and a fuel outlet through which fuel is forced from the / each fuel injector , the / each fuel injector also having a first one-way valve that allows fuel to flow into the fuel chamber from the fuel inlet, while preventing fuel backflow from the fuel chamber to the fuel inlet. and / / each fuel injector additionally having a second one-way valve that allows fuel to flow out of the fuel chamber to Fuel output, impedindoao while refluxing the fuel to the fuel inside dacâmara from the fuel outlet. Internal combustion engine according to any one of claims 3 to 6, characterized by the fact that a sensor is provided to monitor the engine load and to provide the electronic controller with a signal indicating the engine load, the electronic controller calculating Quantum pulses produce in each engine cycle considering the engine load. 8. Internal combustion engine according to claim 7, FEATURED by the fact that a sensor is associated with a crankshaft or camshaft and produces a synchronization signal related to the crankshaft or camshaft rotation. which is used by the electronic controller to trigger pulses generated in this way. 9. Internal combustion engine, characterized in that it comprises: a variable volume combustion chamber, an air intake system for distributing dead air to the combustion chamber, an exhaust system for relaying burnt gas from the combustion chamber to the combustion chamber. atmosphere; a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises: a fuel injector that functions as a positive displacement pump and dispenses a fuel amount that is fixed for any and all injector operations; a controller controlling the operation of the fuel injector, wherein: in each of at least most of the engine cycles, the fuel injector is operated on a plurality of occasions by the controller in response to an increase in engine speed and / or load the engine increases the amount of fuel distributed per engine cycle, increasing the number of times the fuel injector is operated per engine cycle, in response to a decrease in engine speed and / or engine the amount of fuel distributed per engine cycle, reducing the number of times the fuel injector is operated per engine cycle; and the fuel injector comprises: a housing in which a fuel chamber is formed, an electric coil; It is a piston that slides axially into a hole in the β-joint under the action of the electric coil, the piston sliding between two end stops ensuring that the piston has an established displacement distance at each operation. 10. Internal combustion engine, characterized in that it comprises: a variable volume combustion chamber, an air intake system for distributing dead air to the combustion chamber, an exhaust system for relaying burnt gas from the combustion chamber to the combustion chamber. atmosphere; a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises: a plurality of fuel injectors, each of which functions as a positive displacement pump and dispenses a fixed amount of fuel for all and any injector operation, at least one first fuel injector. from the plurality of fuel injectors dispensing a first fuel-set amount different from a second fuel-quantity dispensed by a second fuel injector from the plurality of fuel injectors; a controller controlling the operation of the fuel injector, wherein: in each of at least most of the engine cycles, the fuel injector is operated on a plurality of occasions by the controller in response to an increase in engine speed and / or load the engine increases the amount of fuel distributed per engine cycle, increasing the number of times each fuel injector is operated per engine cycle, in response to a decrease in engine speed and / or engine the amount of fuel distributed per engine cycle, reducing the number of times each fuel injector is operated per engine cycle; Each fuel injector comprises: a housing in which a fuel chamber is formed, an electric coil; It is a piston that slides axially into a hole in the looper under the action of the electric coil, the piston sliding between two end stops ensuring that the piston has an established displacement distance at each operation. Internal combustion engine according to claim 9 or 10, characterized in that the / each fuel injector comprises a predisposition spring acting on the piston. 12. Internal combustion engine according to claim 11, characterized by the fact that the electric coil surrounds the piston. 13. Internal combustion engine according to claim 12, characterized in that an end plate is connected to the piston and extends into a forced piston through an end face of the electric coil. Internal combustion engine according to any one of claims 9 to 13, characterized in that the / each fuel injector comprises a fuel inlet, a fuel outlet, an inlet valve that allows fuel to be drawn to the interior of the fuel chamber from the fuel inlet, while preventing fuel from being expelled from the fuel chamber to the fuel inlet, and a one-way outlet valve that allows fuel to be expelled from the fuel chamber fuel to the fuel outlet, while preventing fuel from being drawn into the fuel chamber from the fuel outlet. 15. Internal combustion engine according to claim 14, CHARACTERIZED by the fact that the one-way inlet valve is a spring-loaded valve. 16. Internal combustion engine according to claim 14 or 15, characterized by the fact that the one-way outlet valve is a spring loaded valve. Internal combustion engine according to any one of claims 14 to 16, characterized by the fact that the one-way inlet valve is provided in a fuel inlet port in the housing. Internal combustion engine according to any one of claims 14 to 16, characterized by the fact that the piston is provided with a fuel inlet passage through which fuel is distributed inside the fuel chamber, and the one-way inlet valve is provided in the fuel inlet passage in the piston, the one-way inlet valve comprising a movable valve element that seals against a seat and the one-way inlet valve arranged so that the thrust of the valve member arising from the piston movement assists both the opening as in closing the unidirectional inlet valve. 19. Internal combustion engine according to claim 18, characterized by the fact that the valve element is a sphere. 20. Internal combustion engine according to claim 18, characterized by the fact that the valve element is a disc. Internal combustion engine according to any one of claims 9 to 20, characterized by the fact that the piston spring biases the piston to engage one end stop and the solenoid acts to slide the piston into engagement with the other stop. against a predisposing force applied by the piston spring. 22. Internal combustion engine according to claim 21, characterized by the fact that the piston spring predisposes the piston to expel fuel from the fuel chamber. 23. Internal combustion engine according to claim 21, characterized in that the piston spring predisposes the piston to drag fuel into the fuel chamber. Internal combustion engine according to any one of claims 9 to 23, characterized in that it comprises a shim providing one end stop. Internal combustion engine according to any one of claims 9 to 24, characterized in that it comprises a shim attached to the piston. A method of manufacturing an internal combustion engine as defined in claim 24 or 25, characterized in that it comprises selecting a dimensioned shim to provide a chosen set displacement distance. A method of manufacturing a plurality of internal combustion engines as defined in any one of claims 9 to 25, characterized in that the engines are provided with fuel injectors which dispense different adjusted amounts of adjusting fuel. different displacement distances for the engine injector pistons, using shims to adjust the piston displacement distances in some and not using any shim in others, and selecting different size shims for different engines to provide different displacement distances to the piston. 28. Internal combustion engine according to claim 1 or 2, characterized in that the / each fuel injector is mechanically driven by a cam action surface, the / each fuel injector comprising a predisposed piston in engagement with the meat action surface by a predisposition spring, and the piston being displaceable by the meat action surface to force fuel out of the fuel injector, the meat action surface comprising a plurality of meat lobes each which can interact with the piston during each engine cycle, and the controller controlling how many of these flesh lobes in each engine cycle can cause the piston to force fuel out of each fuel injector. 29. Internal combustion engine according to claim 28, characterized in that the / each fuel injector comprises a body with a fuel chamber and a fuel outlet through which fuel is forced out of the fuel chamber by piston, the / each fuel injector also having a fuel inlet through which fuel is introduced into the fuel chamber, the / each fuel injector additionally having a one-way inlet valve operable to allow fuel to flow into the fuel chamber from the fuel inlet, while preventing backflow of fuel into the outbound fuel chamber to the fuel inlet, and a one-way outlet valve operable to allow fuel to flow out of the fuel chamber to the wing while preventing fuel backflow into the from the fuel chamber from the fuel outlet. 30. Internal combustion engine according to claim 28, CHARACTERIZED by the fact that the inlet valve can be disabled by the controller and, when disabled, allows fuel to flow back out of the fuel chamber to the inlet. fuel, the movement of the piston when the first one-way valve is disabled is only for dragging fuel from the fuel inlet into the fuel chamber and then expelling the fuel out of the fuel chamber back to the fuel inlet. . 31. Internal combustion engine according to claim 1, characterized in that the / each fuel injector is mechanically driven by a meat acting surface, the fuel injector comprises a flexible diaphragm displaceable by a surface. of meat action to force fuel out of the fuel injector, the meat action surface comprising a plurality of meat lobes which may each cause a flexion of the diaphragm during an engine cycle, and the controller controlling how many These lobes of flesh in each engine cycle cause the piston to force fuel out of each fuel injector. 32. Internal combustion engine according to claim 31, characterized in that the / each fuel injector comprises a body with a fuel chamber and a fuel outlet through which fuel is forced out of the fuel chamber by diaphragm flexion, the / each fuel injector also having a fuel inlet through which the fuel is introduced into the fuel chamber, the / each fuel injector having additionally an operable one-way inlet valve to allow that fuel flows into the fuel chamber from the fuel inlet, while preventing fuel from backing out of the fuel chamber to the fuel inlet, and a one-way outlet valve operable to allow fuel to flow out of the fuel chamber. fuel chamber to the fuel outlet, preventing fuel reflux at the same time l into the fuel chamber from the fuel outlet. 33. Internal combustion engine according to claim 31 or 32, characterized by the fact that it comprises a meat control device capable of rendering one or more meat lobes of the uncontrollable meat action surface, the controller using the flesh control device to control how many lobes of flesh in each engine cycle cause the diaphragm to flex and force fuel out of the fuel injector. 34. An internal combustion engine, characterized in that it comprises: a variable volume combustion chamber, an air intake system for distributing dead air to the combustion chamber, an exhaust system for relaying burnt gas from the combustion chamber to the combustion chamber. atmosphere; a fuel injection system for distributing fuel within the combustion chamber for combustion with the intake air; wherein the fuel injection system comprises: a fuel injector that functions as a positive displacement pump and dispenses a fuel amount that is fixed for any and all injector operations; a controller controlling the operation of the fuel injector, wherein: in each of at least most of the engine cycles, the fuel injector is operated on a plurality of occasions by the controller in response to an increase in engine speed and / or load the engine increases the amount of fuel distributed per engine cycle, increasing the number of times the fuel injector is operated per engine cycle, in response to a decrease in engine speed and / or engine the amount of fuel distributed per engine cycle, reducing the number of times the fuel injector is operated per engine cycle, the fuel injector is mechanically driven by a cam action surface, the fuel injector comprising a piston actuated by a biasing spring is displaceable by the meat action surface, with the piston moving in one direction and to the interior of a fuel injector fuel chamber and the movement of the piston in the other direction forcing fuel out of the fuel chamber, the meat-giving surface comprising a plurality of meat lobes each which can drive the piston during each engine cycle, and the controller controlling how many of the meat lobes in each engine cycle cause the piston to force fuel out of the fuel injector; the fuel injector comprises an outlet fuel by which fuel is forced into the fuel chamber by the piston, and a fuel inlet through which fuel is introduced into the fuel chamber, the fuel injector having additionally a first one-way check valve. operable inlet to allow fuel to flow into the fuel chamber from the fuel inlet at the same time the backflow of fuel out of the fuel chamber to the fuel inlet, and a second one-way outlet valve operable to allow fuel to flow out of the fuel chamber to the fuel outlet while preventing re-flow fuel into the fuel chamber from the fuel outlet; and the one-way inlet valve can be disabled by the controller and, when disabled, allows fuel to flow out of the fuel chamber until the fuel inlet, piston movement when the first one-way valve is disabled serving only to drag fuel from the fuel inlet into the fuel chamber and then to expel the fuel out of the fuel chamber back into the fuel inlet. 35. An internal combustion engine, characterized in that it comprises: a variable volume combustion chamber, an air intake system for distributing exhaust air to the combustion chamber, an exhaust system for distributing intake air to the combustion chamber; combustion; an exhaust system for relaying burnt gases from the combustion chamber to the atmosphere; a fuel injection system for distributing fuel within the combustion chamber for combustion with intake air, wherein the fuel injection system comprises: a plurality of fuel injectors, each of which functions as a pump positive displacement and dispenses an amount of fuel that is fixed for all and any injector operation, at least one first fuel injector from the plurality of fuel injectors dispensing a first set amount of fuel other than a second amount set fuel dispensed by a second fuel injector from the plurality of fuel injectors; a controller controlling the operation of each of the plurality of fuel injectors; where: in each of at least most engine cycles the fuel injectors are operated on a plurality of occasions by the controller, in response to an increase in engine speed and / or load the controller increases the amount of fuel distributed per engine cycle, increasing the number of times fuel injectors are operated per engine cycle, in response to a decrease in engine speed and / or load, the controller reduces the amount of fuel distributed by engine cycle, reducing the number of times the fuel injectors are operated by engine cycle, each fuel injector is mechanically driven by a cam action surface, each fuel injector comprising a piston actuated by a predisposition spring and displaceable by the action surface of the meat, with the movement of the piston in a fuel-dragging direction into a and fuel from the fuel injector and the movement of the piston in the other direction forcing fuel out of the fuel chamber, the meat acting surface comprising a plurality of meat lobes, each of which can trigger the piston during each engine cycle, and the controller controlling how many of the lobes of flesh in each engine cycle cause the piston to force fuel out of the fuel injector, each fuel injector comprises a fuel outlet through which fuel is forced out of the fuel chamber by the piston, and a fuel inlet through which fuel is introduced into the fuel chamber, each fuel injector additionally having a first operable one-way valve to allow fuel to flow into the fuel chamber from the fuel inlet, while implying the outflow of fuel from the fuel chamber to the fuel inlet, and a second one-way valve operable to allow fuel to flow out of the fuel chamber to the fuel outlet, while preventing fuel reflux into the fuel chamber from the fuel outlet. fuel; and each fuel injector one-way valve can be disabled by the controller and, when disabled, allows fuel to flow back out of the fuel chamber to the fuel inlet, piston movement when the first one-way valve is disabled by serving only to drag fuel from the fuel inlet into the fuel chamber and then to expel the fuel into the fuel chamber back to the fuel inlet. 36. Internal combustion engine according to claim 34 or 35, FEATURED by the fact that the one-way inlet valve is provided with an electrically controlled control solenoid, the control solenoid acting on an overlap pin which can fit the first one-way valve to force a25 first open one-way valve. Internal combustion engine according to any one of claims 34 to 36, characterized by the fact that all meat lobes are of an identical height. Internal combustion engine according to any one of claims 34 to 37, characterized by the fact that the meat lobes are provided on a wheel which also has a constant radius section. Internal combustion engine according to any one of claims 34 to 38, characterized by the fact that the piston of each fuel injector has a cam follower which is a roller follower that engages and follows the action surface. of meat. Internal combustion engine according to any one of the preceding claims, characterized in that it has an inlet passage through which air is distributed in an engine combustion chamber, a venturi provided in the inlet passage, a throttling valve in the inlet port and a bypass port that distributes air to the inlet port downstream of the throttle valve, wherein the / each fuel injector distributes fuel to a mixing chamber in which fuel is charged by air from the pass-through. bypass with the mixed fuel and air, then distributed through a nozzle to a venturi neck. 41. Internal combustion engine according to claim 40, CHARACTERIZED by the fact that the air bypass is connected to the atmosphere. Internal combustion engine according to any one of claims 1 to 39, characterized in that it has an inlet passageway through which air is distributed to an engine combustion chamber, a fan provided in the inlet passageway; a non-throttling valve in the inlet passage and a bypass passage distributes exhaust gas or a mixture of air and exhaust gases to the downstream inlet port throttling valve, where the / each fuel injector distributes fuel into a mixing chamber that fuel is charged by gas from the bypass passage with the mixed fuel and gas being then distributed through a nozzle to the venturi neck. Internal combustion engine according to any one of claims 40 to 42, characterized by the fact that the nozzle is a sonic nozzle. Internal combustion engine according to any one of claims 40 to 43, characterized in that the nozzle is an atomising nozzle with a circular orifice. Internal combustion engine according to any one of claims 40 to 43, characterized in that the nozzle is an atomising nozzle with a nozzle arrangement. Method for operation of the internal combustion engine according to any one of Claims 1 to 25 and 28 to 45, characterized in that the method comprises: using / each fuel injector to distribute a plurality of pulses. fuel to the combustion chamber in each engine cycle; vary the number of engine cycle to engine cycle fuel pulses in response to changes in engine speed and / or engine load to thereby control the total amount of fuel distributed to the combustion chamber in each cycle . 47. A method according to claim 46, characterized in that the number of fuel pulses per engine cycle is maintained at a higher first level for a period immediately following the engine start and then is reduced to lower levels for subsequent engine cycles until the engine is restarted.